Rotating electric machines have a stator and a rotor inserted and rotatable within the stator.
In order to insert the rotor into the stator or also to extract the rotor from the stator (for example for maintenance operations), cushions fed with compressed air are provided between the stator and rotor; the rotor is thus slid on these cushions.
Since during sliding the rotor could rotate and fall on the stator and damage it, EP 2 372 884 discloses to provide a guide connected to the rotor shaft by belts and another guide connected to the bearing pedestal lower half.
During introduction or extraction of the rotor with respect to the stator, these guides prevent rotation by sliding one on the other.
Nevertheless, in some cases, the connection made using the belts could be not reliable; thus the risk could exist that the guides are not able to drive the rotor correctly during extraction from or introduction into a stator, such that the rotor can rotate and fall from the cushions on the stator.